Prior to the common adoption of things like machine tools and assembly lines, how similar would two sea fairing ships be in build and design?

Ships have classifications based on a number of factors like length, rigging, number of masts, etc. I’m trying to understand how two ships in the same class would differ.

Would two ships built by the same company be largely identical? Would two ships built to the same specs by a different set of ship builders look or function with significant difference? How pronounced would this difference be across large geographic distances (I imagine a ship built in London would look different from one built in Valencia).